Which of the following functions have a domain of all real numbers? f(x) = -8x^3 - 7
f(x) = |x| + 15
f(x) = -4
f(x) = 1/x
f(x) = 3x - 9
f(x) = cube root of x
f(x) = sqrt(x) + 3
f(x) = -2x^2 - 3x - 9

answer: i'm great at algebra

~coco

step-by-step explanation:

sample answer: you can determine whether each element of the domain is paired with exactly one element of the range. for example, if given a graph, you could use the vertical line test; if a vertical line intersects the graph more than once, then the relation that the graph represents is not a function.

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.